revert: fold-const.c (extract_muldiv_1): Remove bogus TYPE_IS_SIZETYPE special-casing.

2011-09-05  Richard Guenther  <rguenther@suse.de>

        Revert
        2011-08-31  Richard Guenther  <rguenther@suse.de>

	* fold-const.c (extract_muldiv_1): Remove bogus TYPE_IS_SIZETYPE
	special-casing.

From-SVN: r178523

gcc/ChangeLog

+2011-09-04  Richard Guenther  <rguenther@suse.de>
+
+	Revert
+	2011-08-31  Richard Guenther  <rguenther@suse.de>
+
+	* fold-const.c (extract_muldiv_1): Remove bogus TYPE_IS_SIZETYPE
+	special-casing.
+
 2011-09-04  Iain Sandoe  <iains@gcc.gnu.org>
 
 	PR debug/49901

gcc/fold-const.c

@@ -5888,9 +5888,11 @@ extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
 	 multiple of the other, in which case we replace this with either an
 	 operation or CODE or TCODE.
 
-	 If we have an unsigned type, we cannot do this since it will change
-	 the result if the original computation overflowed.  */
-      if (TYPE_OVERFLOW_UNDEFINED (ctype)
+	 If we have an unsigned type that is not a sizetype, we cannot do
+	 this since it will change the result if the original computation
+	 overflowed.  */
+      if ((TYPE_OVERFLOW_UNDEFINED (ctype)
+	   || (TREE_CODE (ctype) == INTEGER_TYPE && TYPE_IS_SIZETYPE (ctype)))
 	  && ((code == MULT_EXPR && tcode == EXACT_DIV_EXPR)
 	      || (tcode == MULT_EXPR
 		  && code != TRUNC_MOD_EXPR && code != CEIL_MOD_EXPR